ABSTRACT The Pilot program has proven to be an important mechanism for the evolution of CSORDA by incorporating new and innovative project areas, new faculty participation, and new technical approaches. The program also has introduced talented UCLA faculty to addiction-related research. The Pilot Core will fund 4 Pilot Projects/year. Pilots have full access to CSORDA resources including the Animal Breeding Core (AB-Core) and the Technical Advancement Core (TA-Core). The TA-Core includes consultation with the Semel Biostatistics Core (SiStat) and Dr. Arthur Arnold for expertise and reagents for the study of sex differences. Logistical management, as well as budgetary and scientific oversight of the Pilot Core, will be the responsibility of the Administrative Core. The Pilot selection process involves a call for proposals and evaluation of the rationale, approach, and rigor of proposals by the Pilot Project Selection Committee, chaired and chosen by Dr. Edythe London. This committee selects project finalists, which are subsequently presented at a biweekly CSORDA meeting. The presentation provides the opportunity for initiating collaborations, as well as critiquing, and optimization of Pilot Projects. Funding is discussed at the Steering Committee leadership meetings, with the Directors making final decisions in consultation with Dr. London and the Advisory Board. Pilots will be funded according to their innovation, research excellence and rigor, as well as impact on substance abuse research. Given equivalent merit, priority will be given to projects most closely related to the theme of the Center or that offer new technologies or research for future CSORDA directions. Pilot progress will be monitored by presentations at a biweekly CSORDA meeting between 6 to 9 months after funding begins. Annual NIH Progress Reports provide documentation of progress. If a second year of funding is requested, a competitive application will be required. The Projects selected for funding during Year 1 of the renewal (with possibility of funding in Year 2) are: I) Pamela Kennedy, Assistant Professor in Psychology, will investigate a switch from goal-directed to habit learning following opioid drug withdrawal and a role for kappa opioid receptors; II) Sotiris Masmanidis, Assistant Professor in Neurobiology, will use silicon microprobe recording technology developed by his group to investigate the perturbation of striatal physiology following withdrawal following chronic opioid administration; III) Kate Wassum, Assistant Professor in Psychology, will explore neural circuits underlying maladaptive reward-seeking decisions in opiate withdrawal; and IV) Carlos Cepeda, Research Professor in Psychiatry, will use miniaturized microscopes from the TA-Core to image calcium activity in the striata of freely-behaving mice following opioid administration. Sex differences will be considered in every Pilot. These 4 Projects all have potential to generate NIDA-related independent research programs or to be incorporated into future renewals of CSORDA. For Years 3-5, we will fund one or two translational (T1 or T2) Pilots, applying for cost sharing with the UCLA CTSI for more substantive funding.